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Old 07-15-2013, 01:32 PM   #1
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Default Checking Roll Center Left To Right Simple Technique

Go and buy get or use 4 of the same Super Soft Springs to put underneath the chassis of like a TCXX Sedan. Take a good weight before this and add it to each top of the Springs/Shocks. Get a mm measurement to make sure all 4 springs are measured at the same compression length for accuracy. Put them on a flat leveled surface as a + design underneath the TCXX one for the front and one for the rear of the chassis and a left and right outside center.

Measure the height of the each spring and compare the heights. That is the Roll Center and where the car will be angled after any turn left or going right and how the TCXX will want to roll and sway in the heavier weight direction.

Now add remove or readjust weight to have all 4 springs at the same height for the same weight distriubution. AKA "The Roll Center" is now all centered.


Last edited by Jay105; 07-15-2013 at 01:53 PM.
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Old 07-15-2013, 01:47 PM   #2
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okay, sounds enough
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Old 07-15-2013, 02:51 PM   #3
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Originally Posted by Jay105 View Post
...That is the Roll Center...
Really, it isn't.
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Old 07-15-2013, 03:09 PM   #4
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Really, it isn't.
We know. He is a troll, please don't feed him
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Old 07-15-2013, 03:26 PM   #5
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Apparently you have a very huge misunderstanding of roll center, what is is, what it does, and this is definitely not a way to calculate it.
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Old 07-15-2013, 03:41 PM   #6
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You've got it all wrong...


A Roll Sinter is what they use to atomically diffuse and compress roll powder into donnuts, duh!
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Old 07-15-2013, 03:48 PM   #7
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i've found that if you take some high tensile steel thread, and tie a loop around where the upper turn buckle attaches to the c hub, and take another piece and loop it in the same fashion through the lower screw in the c hub, and then run both threads out until they intersect at the same angles of the upper and lower arms. next, take that point and measure how far they are away from your center of gravity. write that number down, then tire both of the threads to a handle on an open door. slam the door as hard as you can, noting how many times the car bounces off the floor, and taking into account the wind speed generated by the air conditioning at the track, divide that number by the day of the month it is, minus the number of full moons in the previous month, multiplied by the height of the door handle, minus the height of the table, of course, and then take that number and add it tho the intersect number, divide by pi.

then and only then will you have a true and reliable way to measure roll center.

hope that helps.
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Old 07-15-2013, 03:59 PM   #8
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i've found that if you take some high tensile steel thread, and tie a loop around where the upper turn buckle attaches to the c hub, and take another piece and loop it in the same fashion through the lower screw in the c hub, and then run both threads out until they intersect at the same angles of the upper and lower arms. next, take that point and measure how far they are away from your center of gravity. write that number down, then tire both of the threads to a handle on an open door. slam the door as hard as you can, noting how many times the car bounces off the floor, and taking into account the wind speed generated by the air conditioning at the track, divide that number by the day of the month it is, minus the number of full moons in the previous month, multiplied by the height of the door handle, minus the height of the table, of course, and then take that number and add it tho the intersect number, divide by pi.

then and only then will you have a true and reliable way to measure roll center.

hope that helps.
The cars bouncing though, your measuring dynamic roll center while the OP is clearly talking about linked roll center
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Old 07-15-2013, 04:00 PM   #9
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We don't need this bad information spreading do we? nah. For those of you that might stumble upon this thread... this is not how you do anything in relation to roll center. Heck, you can change and calculate roll center without any springs on the car at all.
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